failing memory in AT&T 6300's

[O05 at PSUVM.BITNET]

I have a lab of 20 AT&T PC6300's.  They have been doing fine, and just
two weeks ago, I started having problems with memory.  Little to my
liking, the chips are soldered on a memory expansion board.  Why AT&T
chose this route, I'll never know, but that doesn't matter.

Does anyone out there know what might cause 4 machines to develop the same
memory symptoms at the same time.  To the best of my knowledge, no spikes,
surges, etc have gone through the room.  It seems to be located in the bank
between 256 and 384k  which would make it the first bank on the memory
expansion card after the 256 on the motherboard.

If you have had similar experiences, please let me know to this newsgroup
or direct E-Mail to o05 at PSUVM.  I'd like to hear from some tech at AT&T
as to the soldering on the card issue.  Looks like our service charges will
be $150 to $200 for each of the machine, and I'm worried about the other 17
machines.

I hope this is not a plot by AT&T re: planned obsolescence, as the
warranty has expired 6 months ago.


                                       Anxiously waiting reply,

                                          Glenn S. Piper
                                          Computer Coordinator
                                          Penn State University
                                          Berks Campus
                                          BITNET: o05 at PSUVM
                                          (215) 320-4819